With the development of economy, science and technology, self-service equipment becomes more and more popular in the financial field (e.g., an ATM in a bank) and in the pan-financial field (e.g., a self-service ticket vending machine, self-service payment machine and the like in the rail transit industry). It can be foreseeable that financial self-service equipment will become closer to people's daily life and higher requirements for the performance of the financial self-service equipment will be made in the future.
In an automatic teller machine (ATM) of a financial institution such as a bank, a valuable document identification device is equipped, which is used to identify the category and authenticity of a current valuable document by identifying the feature of the current valuable document (e.g., banknote). In the ATM, template information of various types of valuable documents are stored, the template information includes the image signal, magnetic signal and thickness signal. When a valuable document is loaded in the identification device, the image signal of the current valuable document is collected by an image sensor of the identification device, the magnetic signal of the current valuable document is collected by a magnetic sensor of the identification device, and the thickness signal of the current valuable document is collected by a thickness sensor of the identification device. Then, the collected image signal, magnetic signal and thickness signal are compared with the image signal, magnetic signal and thickness signal in the template information respectively. If the collected signals are the same as the signals in the template information, it indicates that the current valuable document is real; otherwise, it indicates that the current valuable document is fake. Therefore, based on the identification of an image signal, a magnetic signal and a thickness signal, the identification of the category and authenticity of a current valuable document can be achieved.
In researching and practicing the existing technologies, the inventor of the present invention finds that the prior art has the following disadvantages.
The image signal, magnetic signal and thickness signal stored in template information of an automatic teller machine are collected in a case that multiple sensors are always parallel to the long side of a valuable document. But in practice, the valuable document is often transported in an inclined and deviated manner in the automatic teller machine, thus signals collected by the sensors of the identification device are signals in a condition where the valuable document is inclined or offset. Therefore, when the signals collected in the inclined manner are compared with signals in the template information in the identification device, the identification device determines that the current valuable document is fake or a case where the identification device can not judge the authenticity occurs due to the difference between the signals of the corresponding positions on the current valuable document and in the template information, even though the current valuable document is real.
In the use of an automatic teller machine by a user, once a valuable document is not placed rightly, a case that judgment can not be performed or misjudgment of fake banknote will occur in the identification device of the automatic teller machine, then the user will be asked to places the valuable document again. The identification device can identify and process correctly only after several times of insertion of the same valuable document. Therefore, existing identification devices have lowered identification accuracy for a valuable document, and reduced efficiency, thus causing inconvenience to a user and affecting the usage experience of self-service equipment by a user.
Therefore, how to improve the identification accuracy of an identification device has become the problem mostly needed to be solved currently.